Field of the Invention
The present invention relates to an electro-conductive roller, such as a charging roller, for applying a voltage to perform a process of charging, to a predetermined potential, a surface of an electrophotographic photosensitive member that is a body to be charged, and to a method of manufacturing the same.
Description of the Related Art
In recent years, in an electrophotographic image forming apparatus (electrophotographic apparatus), usage environments and print medium qualities have been diversified, and high quality has been further requested. An electro-conductive roller, such as a charging roller, in a charging device has been energetically developed and improved.
Japanese Patent Application Laid-Open No. H08-234538 discloses a charging roller in a charging device. As illustrated in FIG. 3, this charging roller 100 includes an electro-conductive roller body 104 (or a blade-shaped body or a pad-shaped body) that includes a conductive core metal 101 connected to a power source device via an electrode terminal 102. A thread member 103 composed of an insulative material is wound on the circumferential surface of the roller body 104 at certain intervals to form convexities. Furthermore, one or more low resistive conductive wire-shaped electrode members, such as tungsten wires, gold wires or copper wires, having a smaller diameter than that of the insulative thread member are arranged alternately with the insulative thread member 103, thereby forming an electrode body.
When such a charging roller is pressed against and in contact with an image forming member (photosensitive member), the thread insulative member serves as a spacer.